This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Recent studies have found that the disease B-type chronic lymphocytic leukemia (B-CLL) can be divided into two subgroups based on lg V gene mutation status and CD 38 expression. The patients in these two groups follow different clinical courses. This proposal is designed to understand more precisely how these two broad categories of B-CLL cases differ.